Drowsy Driving on Long Trips

Short answer: Drowsy driving is common on long trips and hard to count from police reports alone. NHTSA estimated about 91,000 police-reported drowsy-driving crashes in 2017, with roughly 50,000 people injured and nearly 800 deaths, and calls that an underestimate. [S01] AAA Foundation modeling for 2017–2021 put drowsiness in an estimated 17.6% of fatal crashes. [S03] The only reliable protection is enough sleep before you go; coffee and short naps help only briefly. [S01] [S02]

Long drives to appointments, treatment centers or lodging can stack late nights, early mornings and monotonous highways. This guide covers warning signs, what agencies report about crash risk and practical steps that actually help. It is general travel-safety guidance, not medical advice about any disease or treatment. Pair it with planning tools such as our Appointment Logistics Planner and tips for eating well while traveling.

Drowsy-driving checklist for a long trip

How big is the risk?

NHTSA says precise counts are hard because investigators cannot always prove drowsiness. [S01] Its estimate for 2017 was about 91,000 police-reported crashes involving drowsy drivers, about 50,000 people injured and nearly 800 deaths. [S01] The agency notes broad agreement that those figures undercount the problem. [S01] Its drowsy-driving page also cites 644 deaths from drowsy-driving-related crashes in 2024. [S01]

The AAA Foundation for Traffic Safety used in-depth crash data and a model to estimate drowsiness in all U.S. fatal crashes involving passenger vehicles from 2017 through 2021. [S03] It estimated that 17.6% of those fatal crashes involved a drowsy driver, and that about 29,834 people were killed in drowsy-involved fatal crashes over that five-year span. [S03] CDC/NIOSH summarizes related research saying as many as one in five fatal crashes involve driver fatigue. [S02]

When crashes tend to happen

NHTSA links drowsy-driving crashes to three patterns: [S01]

1. They happen most often between midnight and 6 a.m., or in the late afternoon, when circadian alertness dips.
2. They often involve a single driver, no passengers, high speed and no braking.
3. They frequently occur on rural roads and highways.

AAA Foundation analysis found the largest number of fatal drowsy-driving crashes between 11 p.m. and 2:59 a.m., and the highest share of drowsy drivers among those who crashed between 3:00 and 6:59 a.m. [S03]

Warning signs you should not ignore

Fatigue changes how you drive before you fully fall asleep. CDC/NIOSH lists effects such as nodding off, slower reactions, poor decisions, drifting from your lane, tunnel vision, microsleeps lasting from a fraction of a second up to about 30 seconds, and forgetting the last few miles. [S02] NHTSA adds crossing roadway lines or hitting a rumble strip as cues to stop, especially if you are alone. [S01]

A microsleep can be enough to leave the road. NHTSA notes that a four- or five-second microsleep at 55 miles per hour covers more than 100 yards. [S01]

Rumble strips and lane-departure alerts are helpers, not permission to keep driving while exhausted. If you hit a rumble strip more than once, treat that as a stop signal. [S01]

What actually helps

Sleep first

Getting enough sleep every day is the only true protection against drowsy driving, according to NHTSA. [S01] NHLBI says adults should aim for 7 to 9 hours a night, and that teens need 8 to 10 hours. [S05] NHLBI also warns that people cannot safely "learn" to function on little sleep. [S04] Before a long family or caregiver trip, plan a real night of sleep rather than loading the car late. [S01]

Stops, swaps and timing

• Build rest stops into the itinerary before you leave, not only when you feel desperate.
• Share driving if more than one licensed, rested adult is available.
• Avoid driving alone through midnight to 6 a.m. when you can. [S01]
• If treatment or lodging forces early or late travel, consider another night nearby rather than pushing through. Our hotel vs Airbnb long-stay guide covers longer lodging choices.

Caffeine has limits

Coffee or energy drinks alone are not enough. [S01] They may make you feel more alert for a short time while you remain more impaired than you think. [S01] NHTSA's short-term advice, if you start to feel sleepy, is one to two cups of coffee plus a short nap of about 20 minutes in a safe place such as a lighted rest stop. [S01] CDC/NIOSH similarly says to pull over, drink coffee and take a 15- to 30-minute nap, and stresses that the effect is temporary because only sleep cures fatigue. [S02]

Medicines and alcohol

Check prescription and over-the-counter labels for drowsiness warnings before you drive. [S01] [S06] FDA lists side effects that can impair driving, including sleepiness, blurred vision, dizziness and trouble focusing, and notes that some sleep medicines can still impair you the next morning. [S06] NHTSA also warns that alcohol interacts with sleepiness and increases drowsiness and impairment, so avoid drinking before driving. [S01] AAA Foundation data similarly found drowsiness more common among drivers who had been drinking than among those who had not. [S03]

If a medicine you need makes driving unsafe, ask your care team about timing, dose or another way to travel. Guides on how to pack medications and airport wheelchair assistance can help when flying is the better option.

When not to drive

Do not get behind the wheel if any of these apply:

• You slept far less than your usual 7–9 hours and feel heavy-eyed. [S05] [S01]
• You are already crossing lanes, hitting rumble strips or forgetting stretches of road. [S01] [S02]
• A medicine, including some allergy, cold, pain or sleep products, lists driving warnings. [S06]
• You would be the only driver through the overnight circadian low after a short night. [S01]
• You have been awake roughly 17 hours or more; CDC/NIOSH notes impairment around that point can resemble a blood alcohol content of about 0.05, and around 24 hours awake about 0.10. [S02]

In those cases, delay departure, switch drivers, book an extra night or use another travel mode. For appointment logistics that reduce last-minute all-nighters, use the Appointment Logistics Planner. On longer flights, compression socks for flying cover a separate travel-health topic.

Caregivers and shared driving

Medical trips often involve a patient and a caregiver sharing one car. Decide before you leave who drives which leg, and treat a short night of sleep as a reason to switch drivers—not a reason to "tough it out." NHTSA notes that teens are especially vulnerable when their sleep need is high and trip distances grow, so delay driving until they are well rested. [S01] The same logic applies to any adult who has been awake through early-morning treatment or late discharge.

If only one person can drive and that person is depleted, overnight lodging near the appointment can be safer than a midnight return. Our hotel vs Airbnb long-stay guide covers longer stays; even one extra night can remove an overnight drive.

Pack medicines so dosing times do not collide with driving. FDA warns that some allergy, cold, pain and sleep products impair driving, sometimes into the next day. [S06] Keep the labels with you and confirm timing with your care team before departure. [S01]

Putting it together for medical travel

Treatment calendars often mean early check-ins and late discharges. Treat sleep as part of the trip plan: protect the night before a long drive, schedule stops, and decide in advance who drives which leg. Daytime meals and hydration on the road pair with the habits in eating well while traveling. Sun glare and heat on summer drives are separate issues covered in sun safety basics.

If fatigue shows up mid-trip, the safe move is to stop—not to "push through" with another coffee.